It's great to hear that you're interested in writing for the site! Make sure to create a sandbox page for yourself to work on your stuff, and get any drafts you write up there shown to the IRC chat and/or the drafts forums for feedback before you post to the mainsite.

The chat is also a great place to hang out at and meet fellow Foundation site members. You can get a feel for the real-time critique given there, and also toss around ideas with others.

Furthermore, if you've got any questions, comments, or concerns, feel free to PM a staff member.